Cosmodrive

Cosmodrive is superluminal (faster-than-light) travel based on metric engineering and quantum vacuum manipulation.

Theory

The physical basis behind cosmodrive propulsion comes out of superfluid vacuum theory and its successors in the mid-to-late twenty-first century Terran calendar, before the Wormhole Rush. These theories view space as permeated by a quantum vacuum, and the finite speed of light as a consequence of photons scattering off this vacuum. At the outset of the Wormhole Rush, as part of the process for creating and inflating wormholes, a means of creating altered vacuum states was discovered. This enabled the projection of wormholes at superluminal speeds, and later, spacecraft.

Operation

A shipboard cosmodrive is somewhat similar to an impeller warp and uses some of the same equipment, but instead of creating a region of distorted space around the ship, creates a bubble of altered vacuum which "boosts" the ship's intrinstic velocity to superluminal speeds.

Thus, in order for a ship to engage its cosmodrive it must be traveling fast enough to end up across the light barrier after activation; for modern vessels and drives this is typically in the range of 10 to 30% lightspeed, fast enough to give reasonable travel times. The process of reaching this speed is known as a run-up in astrogation parlance, with an analogous run-down performed at the end to decelerate into the destination system. As expected, reaching this jump speed requires a high-grade sublight propulsion system--only a gravitational impeller will suffice, and even then, even with multiple gees of thrust, several weeks to months of continous acceleration are required on each end.

Once at speed, the jump is initiated, effectively dropping the ship out of the ordinary universe while it travels in its pocket of altered vacuum. Astrogation and mid-course corrections are not possible while the cosmodrive is engaged, thus a crew must take great care in calculating their trajectory before turning it on, and will often drop out of cosmodrive briefly to make a correction burn towards the end of their trip.

History

The use of vacuum manipulation to move spacecraft was theorized early in the Wormhole Rush, but it was not until the invention of gravitational impellers in the mid-Second Interstellar Period that a propulsion system was had capable of reaching the necessary jump velocity. Cosmodrive technology was infamous in this time for its role in strategic deterrence--so-called arsenal ships would carry payloads of RKVs up to nearlight speed, awaiting a signal to fly them to an enemy homeworld and lay it to waste. The breakdown of this deterrence led to the Interstellar Dark Ages.

Consequently, the Stellar Compact rates cosmodrives and impellers as Class II Controlled Technologies, forbidding their use as weapons, and requiring its member states subject captains of impeller ships to strict psychological screening, to ward off any would-be kamikaze terrorists.

In the Unified Era, cosmodrives are used to access solar systems not (yet) connected to the stargate network of the Starweb. Common destinations include lost colonies, paleotech sites, and objects of astrophysical exploration.